The brunette babes made an appearance at the Barnes and Noble bookstore at The Grove in Los Angeles tonight to sign fans' copies of their book Rebels: City of Indra: The Story of Lex and Livia, and as usual, they were quite the sight to see.

Kendall donned an all-white jumpsuit with a sheer top that exposed her midriff and wavy tresses, while her younger sis kept it playful in a studded spaghetti strap tank top, dark skirt and black hat that accentuated her bright blue tips.

"On our way to @BNbooks@TheGroveLA for our book signing, see you there!! XOXO #REBELSthebook," Kendall tweeted, while Kylie wrote, "Almost ready for our book signing at @BNbooks @TheGroveLA tonight!! It starts at 7pm, so get over here quick! #REBELSthebook."

The gripping, young-adult tale is set in a futuristic, dystopian city and follows two girls as they reluctantly team up on a quest, only to discover more there's much more to their mission than they imagined.

"Kylie and I love the creative challenge and are thrilled to have been given the opportunity to share this story," Kendall had said when announcing the release of the book, while her sister added, "We can't wait to share these characters and the world we created with readers everywhere. We are so excited!"

Karen Hunter, publisher of Karen Hunter Publishing, said, "The story that Kendall and Kylie crafted is a thrill ride—one that their fans and fans of this genre won't be able to put down."

Tune-in to the season premiere of Keeping Up With the Kardashians on Sunday, June 8 at 9/8c only on E!